Flash concentration of solutions containing polyolefins

Claim 1

IN A FLASH CONCENTRATION PROCESS IN WHICH A DILUTE SOLUTION OF A NORMALLY SOLID POLYOLEFIN SOLUTE DISSOLVED IN A HYDROCARBON SOLVENT AT A PRESSURE SUFFICENT TO MAINTAIN IT IN A LIQUID STATE IS FED INTO A FLASH ZONE, IS FLASHED BY REDUCING THE PRESSURE THEREON IN SAID ZONE, SAID SOLUTION BEING OF SUFFICIENT TEMPERATURE TO IMMEDIATELY VAPORIZE A PORTION OF SAID HYDROCARBON SOLVENT IN SAID ZONE, THE RESULTING VAPOR AND LIQUID ARE REMOVED SEPARATELY FROM SAID ZONE, AND SAID VAPOR IS CONDENSED TO RECOVER SOLVENT, WHEREIN THE CONDENSERS ARE NORMALLY SUBJECT TO RAPID PLUGGING BY DEPOSIT OF SOLUTE ENTRAINED IN SAID VAPOR, THE IMPROVEMENT COMPRISING THE STEPS OF RECYCLING A MAJOR PORTION OF THE LIQUID REMOVED FROM SAID ZONE TO FEED WITHOUT HEATING BEFORE IT ENTERS SAID ZONE, SPRAYING THESE COMBINED LIQUIDS IN THE TOP OF SAID ZONE DOWNWARDLY THROUGH THE RISING VAPOR AGAINST THE SURFACE OF THE LIQUID IN SAID ZONE THEREBY SUBSTANTIALLY REDUCING THE AMOUNT OF POLYOLEFIN SOLUTE CARRIED OUT OF SAID ZONE WITH SAID VAPOR AND THEREBY SUBSTANTIALLY INCREASING THE TIME BEFORE SAID CONDENSERS PLUG.